©1999, 2002, Joyce Bischoff, All rights reserved. Conducting Data Warehouse Assessments Joyce Bischoff Bischoff Consulting, Inc. Hockessin, Delaware 302-239-7202

©1999, 2002, Joyce Bischoff, All rights reserved.

Conducting Data Conducting Data Warehouse AssessmentsWarehouse Assessments

Joyce Bischoff

Bischoff Consulting, Inc.

Hockessin, Delaware

302-239-7202


• Definition• Reasons for assessments• Assessment Approach

– Building the Team– Assembling Information– Using Leading Questions– Interviewing managers, users,

user support, technical staff

• Reporting the findings– Assessment Topics

• Summary

AgendaAgenda


Dynamic toolStructured approach

for DW evaluation

May be educationalMore than a checklist!

Needs cooperative

atmosphere

No “right” answers-Answers depend upon participants!

What is it?What is it?


To ensure:• Business objectives are met• Users are satisfied• Technical staff is working effectively• Corporate infrastructure is in place• DW / DM processes are working effectively• To ensure that tradeoffs are understood

– Data currency & integrity– Data availability– User satisfaction– Performance– Flexibility

Data Warehouse Assessments- Why?Data Warehouse Assessments- Why?


ASSESSMENTS• Readiness Assessment• In-Development

Assessments

• Post-implementation Assessment

DESIGN REVIEWS• Architectural Review• Data Warehouse Data

Model Review• Data Transformation &

Cleansing Review• Programming Review• Code/Utility Review• Performance Review• Includes all of the

above

Scheduling Assessments and ReviewsScheduling Assessments and Reviews


Gather information & Identify problems

InvestigateRecommendationsto correct problems

» JAD sessions» Interviews» Questionnaires» Documentation

Assess the current situation

The ApproachThe Approach


Is the datawarehouse a success?

Executives &Managers

Users

Technical Staff

The ApproachThe Approach


• Team members– Need mix of skills to examine Assessment Topics– Must provide objective evaluation– Need interviewing skills and technical skills– Should understand best practices in the industry– Makes recommendations based on best practices

• Each topic needs an assigned leader • Team may include 2-6 people (average)

What about politics??

Building the TeamBuilding the Team


• Project scope & documented requirements• Business objectives of DW• Organization chart, including list of data warehouse

staff, key managers, and users• Roles & responsibilities and how assigned• Training programs for users and DW team • DW architecture description, including

data marts, ODS, DW, and relationships• Standards, guidelines, & procedures

Assembling InformationAssembling Information


• Asking the right questions at the right time is the basis for successful assessments

• Leading questions provide a basic check list and should be prepared in advance

• Drill down as far as necessary to obtain needed information

• DW assessments require more than

a checklist. . . . but a checklist helps!

Using Leading QuestionsUsing Leading Questions


• Questions:– Must be tailored for your situation

– Printed questionnaires; may be anonymous

– JAD sessions

– One-on-one interviews

– Always ask for additional comments

• Leading questions are only a starting point

• Answers point the way to

identifying weaknesses and

proposing improvements ?

Using Leading QuestionsUsing Leading Questions


DW Strategy

Business Value

UserSatisfaction Organizational

Issues

Business Requirements

DevelopmentMethodology

DWArchitecture

Standards & Guidelines

VendorRelationships

Assessment TopicsAssessment Topics


MetadataStrategy

DataModeling

Database Design

DWAdministration

Data Access & Delivery

Performance & Capacity

FuturePlanning

Data Management

Assessment TopicsAssessment Topics


• Is the data warehouse a success?– Business value– Return on investment– Organizational issues

• From your perspective, what are

its strong and weak points?

• Did it meet strategic objectives?

Which ones?

• Future plans for the DW or DM

• Are there particular persons that we should be sure to talk with (in addition to our present list)?

Sample Questions for Executives & ManagersSample Questions for Executives & Managers


• Why was the DW / DM built?• Discuss the following areas with appropriate members of

the technical staff:– User satisfaction– Standards & Guidelines– Metadata strategy– Data management processes– Performance and capacity planning– Data access and delivery issues– Data modeling & database design– Future planning

Discuss the process & results of the processesfor each technical area

Sample Questions for Technical StaffSample Questions for Technical Staff


• Project starts with user requirements and will be judged against them

• Why was the data warehouse built?• Were your special requirements considered? • Business value realized? Money saved? Improved efficiency?

Most important benefit realized?• What is the most important question that you cannot ask?• Technical staff responsive to new requirements?• Level of satisfaction with DW/DM, ease of

use, end-user tools, availability, etc.?• Is data easy to use?

Sample Questions for UsersSample Questions for Users


• Adequately staffed?• Types of problems encountered?• Do you have problems addressing problems?• Adequate support from the technical staff?• Users adequately trained in data and tools?• User expectations well managed?• How could it be improved?

End User Support Help DeskEnd User Support Help Desk


• Summarize findings of interviews, JAD sessions, questionnaires, and analysis of documentation

• Cover each assessment topic that was addressed during the review

• Following pages summarize sample issues in each subject area

Building the ReportBuilding the Report


What is the data

warehouse strategy?

Is it designed to fundamentally change

the way business decisions are made?

Does the strategy allow for

iterative development with increasing

benefits after each cycle?

DW StrategyDW Strategy


How / who sets

priorities for DW

development?

Review procedures

for evaluating ROI

Business benefits

from using DW, DM,

or ODS?

Business ValueBusiness Value


• Review processes for:– Gathering requirements– Determining new requirements– Keeping requirements current– Identifying gaps between stated requirements

and actual capabilities

• How well are current requirements met?• Suggest ideas for encouraging creative use

of existing data

Business RequirementsBusiness Requirements


• Has an “official” strategic alliance been created between the users and IT staff?

• Is there a high level user sponsor?• Mission and objectives in line with corporate business

objectives?• Sufficient budget allocated?• Organizational roadblocks?• Who are the users? How will they be involved?

• How will the users be trained and supported? • What are the users’ expectations?

Organizational Issues: Leading QuestionsOrganizational Issues: Leading Questions


• Process in place for responding to user complaints about performance, data quality, data availability, data integrity, and consistency?

• Does the technical staff have the skills needed to support the DW?

• Roles and responsibilities defined and assigned?

• Source data documented?

• What is the quality of the source data?

• How will technical personnel track data usage and changing user requirements?

• End-user tools and development tools selected?

Organizational Issues: Leading QuestionsOrganizational Issues: Leading Questions


• How are data warehouse projects planned?• Does everyone understand definitions of

DW and data warehouse technology?• Effective methodology in place?

– Are RAD techniques used?

– All phases and activities time-boxed?

– Methodology flexible enough to

accommodate projects of varying

sizes, ODS, DM, DW?

DW MethodologyDW Methodology


• Review use of DW, DM, ODS and their relationships

• Review effectiveness of current hardware / software / DW tools

• Scalability?

• How does the data flow?

DW ArchitectureDW Architecture


• Do you track data usage? Table level? Column level? Row level?

• Do you track trends in growth of specific tables?• How do you allocate space?• How do you determine what data

needs to be audited?• Do you know which users use which data?• Do you know which access paths are needed by various

users? How do you determine this? • What is your process for implementing new access paths?

Data ManagementData Management


• Review process of selecting source data, extraction, cleansing, and transformation

• Review processes for maintaining data quality

• Are there problems with data consistency?

• Identify opportunities for data

integration

• How do you handle requests

for additional data?

• How do you handle backup, recovery,

reorganization, etc.?

Data ManagementData Management


• How do you measure performance in the DW?

• Do you have service level agreements?– On what are they based?

• How do you measure user satisfaction with performance?

• How do you measure trends in performance?

• Comparisons of today vs. another day? This week vs. last week?

• How do you identify hot spots in databases?

• How do you identify candidates for re-partitioning?

• Do you have a scalable environment in terms of hardware and software?

Performance & Capacity PlanningPerformance & Capacity Planning


• Review existing metadata strategy– Locations and consistency between

locations– Processes for keeping it current– Accessibility to users and technical

personnel

Metadata StrategyMetadata Strategy


• Review standards, guidelines, and procedures, if available– Requirements gathering and documentation– Architecture guidelines – Data and metadata– Database design, development, administration– Development– Data quality, cleansing, transformation– etc.

• Assess effectiveness

DW Standards, Guidelines, and ProceduresDW Standards, Guidelines, and Procedures


DSS

EIS

Ad Hoc

Traditional

DataWarehouse

DataMart

DataMart

DataMart

DataMining

Data Access & DeliveryData Access & Delivery


• What types of data modeling are used?• Are they effective?• Compare with best practices• Where are models stored?• Are they integrated and reusable?• Do users have access to data models?

– Which ones?– How do they use them?

Data ModelingData Modeling


• Review processes used to design databases– Usage of data models – Selection of DBMS– Design review processes (if applicable)– Design guidelines for specific DBMSs

• Review database designs for selected subject areas– Multi-level data architecture?– Managed data redundancy?

• Compare with best practices

Database DesignDatabase Design


• Compile the results of all interviews, JAD sessions, questionnaires, reviews, and analysis of documentation

• Include the topic, findings, and recommendations for each area analyzed

• Level of detail will depend upon concerns raised by interviewees– Concerns will require deeper analysis in selected areas– Findings will depend upon the

persons interviewed!

DW Assessment ReportDW Assessment Report


Executives &Managers

UsersTechnical Staff

• Design• Development• Administration• Organization

• Management processes• Strategy

• Business Value• ROI

Summary of the ProcessSummary of the Process

Documents

©1999, 2002, Joyce Bischoff, All rights reserved. Conducting Data Warehouse Assessments Joyce Bischoff Bischoff Consulting, Inc. Hockessin, Delaware 302-239-7202